Monitoring and control of complex industrial machines generally requires many sensors of various types (vibration, temperature, pressure, etc.) and control devices (i.e., for switches, valves and actuators) distributed at various locations on or near the machine. Typically, such sensors and control devices are connected to monitoring and control systems in an industrial plant via a communication network. Disadvantages associated with prior communication networks in such applications include:                data transfer distance is limited;        many power supplies are required to power widely distributed sensors and control devices, which contributes to higher costs;        the length of signal lines between sensors and sensor modules tends to be long, contributing to noise problems on low-amplitude signals; and        because the conversion from analog signals to digital signals occurs at the sensor module, long signal lines between sensors and sensor modules further increase the probability of noise.        
What is needed, therefore, is a machine monitoring and control network that alleviates the problems associated with fieldbus networks.